Dose-dependent incidence of agranulocytosis in patients treated with methimazole and propylthiouracil.

Agranulocytosis is a serious adverse effect of methimazole (MMI) and propylthiouracil (PTU), and although there have been reports suggesting a dose-dependent incidence in relation to both drugs, the evidence has not been conclusive. The objective of our study was to determine whether the incidences of agranulocytosis induced by MMI and PTU exhibit dose-dependency. The subjects were 27,784 patients with untreated Graves' disease, 22,993 of whom were on an antithyroid drug treatment regimen for more than 90 days. Within this subset, 18,259 patients had been treated with MMI, and 4,734 had been treated with PTU. The incidence of agranulocytosis according to dose in the MMI group was 0.13% at 10 mg/day, 0.20% at 15 mg/day, 0.32% at 20 mg/day, and 0.47% at 30 mg/day, revealing a significant dose-dependent increase. In the PTU group, there were 0 cases of agranulocytosis at doses of 125 mg/day and below, 0.33% at 150 mg/day, 0.31% at 200 mg/day, and 0.81% at 300 mg/day, also revealing a significant dose-dependent increase. The incidence of agranulocytosis at MMI 15 mg and PTU 300 mg, i.e., at the same potency in terms of hormone synthesis inhibition, was 0.20% and 0.81%, respectively, and significantly higher in the PTU group. Our findings confirm a dose-dependent increase in the incidence of agranulocytosis with both drugs, but that at comparable thyroid hormone synthesis inhibitory doses PTU has a considerably higher propensity to induce agranulocytosis than MMI does.

Clinical features of moyamoya disease with Graves' disease: a retrospective study of 394,422 patients with thyroid disease.

Graves' disease has been reported to affect the clinical features of moyamoya disease (MMD), an occlusion of the circle of Willis. This study aimed to clarify the characteristics of MMD in patients with Graves' disease. This was a single-center, retrospective study. The prevalence and clinical features of MMD patients among all patients with thyroid disease who visited Ito Hospital from January 2005 to December 2019 were evaluated. The relationship between MMD and hyperthyroidism was analyzed in new-onset Graves' disease patients during the same period. Of all 394,422 patients with thyroid disease, 88,180 had Graves' disease, and 40 had MMD with Graves' disease, i.e., the prevalence was 45.36 per 100,000 patients with Graves' disease (0.0454%). The median age at onset of MMD was 39 years (interquartile range, 31-54 years), with a male to female ratio of 1:12. The most common time that MMD was diagnosed was within 1 year after the onset of Graves' disease, in 9 of 40 patients (22.5%), and 19 of 40 patients (47.5%) underwent bypass surgery for MMD. In MMD with Graves' disease, headache was the most frequent symptom, and ischemic types of stroke and bilateral lesions were common. Of 23,347 patients with new-onset Graves' disease, 7 were diagnosed with MMD and the incidence of MMD was 5.94 patients per 100,000 person-years. Most patients developed MMD symptoms during hyperthyroidism. Although MMD is a rare condition, it should be noted that it can occur with Graves' disease.

Radioiodine uptake after monotherapy with potassium iodide in patients with Graves' disease.

The effect of potassium iodide (KI) on radioiodine uptake (RAIU) before radioisotope therapy in Graves' disease (GD) patients was investigated. A total of 82 patients who had been treated with KI monotherapy before 24-hour RAIU (24 h RAIU) were evaluated and 354 of those who had been treated with thiamazole (MMI) monotherapy were extracted from the 1,130 GD patients who were identified as having had appropriate iodine restriction based on urinary iodine excretion. Urinary iodine excretion (UIE) <200 µg/day was confirmed in all subjects. Propensity score-matching was performed to identify the difference in 24 h RAIU between the KI group and the MMI group. In addition, multiple regression analysis was performed to evaluate related to 24 h RAIU. Propensity score-matching resulted in 57 matched patients in each group. After matching, 24 h RAIU was still significantly lower in the KI group than in the MMI group (median 53% (interquartile range 47-61%) vs. 63% (56-66%); p = 0.001). In addition, KI monotherapy was weakly negatively correlated with 24 h RAIU, whereas the female sex and FT3 were very weakly positively correlated on multiple regression analysis. The results suggest that KI monotherapy likely suppressed 24 h RAIU more than MMI monotherapy in GD patients with appropriate iodine restriction, given the difference in the mechanism of hormone suppression.

Establishment of reference intervals for fT3, fT4, and TSH levels in Japanese children and adolescents.

The present study aimed to establish new reference intervals (RIs) for serum free triiodothyronine (fT3), free thyroxine (fT4), and thyroid stimulating hormone (TSH) levels in Japanese children and adolescents aged 4 to 19 years. A total of 2,036 (1,611 girls, 425 boys) participants were included over a 17-year period; they all tested negative for antithyroid antibodies (TgAb, TPOAb) and were found to have no abnormalities on ultrasonography. RIs were determined by nonparametric methods. The results showed that serum fT3 was significantly higher in the 4-15-year-olds than in the 19-year-olds. The serum fT4 was significantly higher in the 4-10-year-olds than in the 19-year-olds. The serum TSH was significantly higher in the 4-12-year-olds than in the 19-year-olds. All of them gradually decreased with age to approximate the adult levels. The upper limit of TSH was lower in those aged 13 to 19 years than in adults. The differences were examined by sex. The serum fT3 was significantly higher in boys than in girls between the ages of 11 and 19 years. The serum fT4 was significantly higher in boys than in girls between the ages of 16 and 19 years. There did not seem to be any sex difference in those under 10 years of age. In conclusion, serum fT3, fT4, and TSH levels in children and adolescents differ from those in adults. It is important to evaluate thyroid function using the new RIs that are appropriate for chronological age.

Incidence and risk factors for Graves' orbitopathy in patients who underwent anti-inflammatory and immunosuppressive treatment during medical treatment for Graves' disease: investigation of 1,553 cases with newly diagnosed Graves' disease and proposal of a predictive score.

Appropriate administration of anti-inflammatory and immunosuppressive treatment (AIIST) is important for patients with Graves' orbitopathy (GO). This study aimed to clarify the incidence and risk factors for GO treated with AIIST and propose a predictive score, among newly diagnosed Graves' disease (GD) patients in Japan. A total of 1,553 GD patients who were newly diagnosed during the year 2011 were investigated. AIIST included local and/or systemic glucocorticoid administration and retrobulbar irradiation. A multivariable Cox proportional hazards model was used to investigate the risk factors for GO underwent AIIST during medical treatment, including at diagnosis, of GD. Then, a GO score was created by summing each point assigned to risk factors based on their coefficient obtained in the Cox model. AIIST was administered to 107 patients (6.9%). The risk factors and hazard ratios for GO underwent AIIST were: age (per 10 years), 1.32 (95% confidence interval: 1.16-1.50), p < 0.0001; TSH binding inhibitory immunoglobulin (TBII) (per 10 IU/L), 1.33 (1.15-1.54), p = 0.0001; and thyroglobulin antibody (TgAb) negativity, 2.98 (1.96-4.59), p < 0.0001. The GO score, ranging from 0 to 8 points, showed moderate performance (area under the curve: 0.71, cut-off value: 5 points, sensitivity: 0.76, specificity: 0.59, positive predictive value: 0.12, negative predictive value: 0.97). AIIST was performed for patients with active manifestations of GO in 6.9% of newly diagnosed GD patients. The risk factors for GO underwent AIIST were higher age, higher TBII, and TgAb negativity. The GO score based on these factors may be useful in managing GO.

Survey of the actual administration of thiamazole for hyperthyroidism in Japan by the Japan Thyroid Association.

To clarify the actual administration of thiamazole (MMI), the first choice of antithyroid drugs, the actual therapy provided by the Japan Thyroid Association (JTA) members for the following conditions was surveyed. The subjects included adult patients, pregnant women, and pediatric patients with Graves' disease who visited each medical institution from September 2019 to February 2020. Initial doses, frequency of administration, maintenance doses, maximum doses, consultation intervals for pregnant women, and dosages administrated to breastfeeding mothers were surveyed. The total number of cases collected was 11,663. Administration of 15 mg once a day was the most common initial therapy, constituted 74.4% (2,526/3,397 cases) of adults, 33.8% (44/130) of pregnant women, and 50.8% (61/120) of children. The maintenance dose before discontinuation was equivalent to 2.5 mg/day in 52.3% (3,147/6,015). The most common maximum dose for adults and children was 30 mg/day, administrated to 57.5% of adults (223/388) and 59.6% (28/47) of children; for pregnant women, it was 15 mg/day, administrated to 71.1% (27/38). The most common consultation interval for pregnant women was every four weeks (32.1%, 341/1,063). In lactating mothers, the dose was 10 mg/day or less in 366 of 465 cases (78.7%). Breastfeeding was also allowed 4-6 hours after the administration of 15-20 mg/day in 69 patients (14.8%). Breastfeeding was prohibited in 26 patients (5.6%). In conclusion, initial MMI therapy was started with 15 mg once a day in most patients, and MMI was also administrated to lactating mothers following the Graves' disease treatment guidelines by the JTA.

Prediction model of Graves' disease in general clinical practice based on complete blood count and biochemistry profile.

Although untreated Graves' disease (GD) is associated with a higher risk of cardiac complications and mortality, there is no well-established way to predict the onset of thyrotoxicosis in clinical practice. The aim of this study was to identify important variables that will make it possible to predict GD and thyrotoxicosis (GD + painless thyroiditis (PT)) by using a machine-learning-based model based on complete blood count and standard biochemistry profile data. We identified 19,335 newly diagnosed GD patients, 3,267 PT patients, and 4,159 subjects without any thyroid disease. We built a GD prediction model based on information obtained from subjects regarding sex, age, a complete blood count, and a standard biochemistry profile. We built the model in the training set and evaluated the performance of the model in the test set by using the artificial intelligence software Prediction One. Our machine learning-based model showed high discriminative ability to predict GD in the test set (area under the curve [AUC] 0.99). The main contributing factors to predict GD included age and serum creatinine, total cholesterol, alkaline phosphatase, and total protein levels. We still found high discriminative ability even when we restricted the variables to these five most contributory factors in our prediction model (AUC 0.97) built by using artificial intelligence software showed high GD prediction ability based on information regarding only five factors.

A case of macro-TSH consisting of IgA-bound TSH.

An asymptomatic, 68-year-old Japanese man visited our hospital for further examination of subclinical hypothyroidism. At the first visit, the serum TSH level was markedly elevated (36.6 µIU/mL), but the serum level of free T4 was within the reference interval. Thyroid dysfunction due to dietary iodine excess was initially suspected. However, even after iodine restriction, his thyroid function tests were the same as at the first visit, which suggested false elevation of the TSH level. The TSH levels were compared among three different measurement systems, which showed a similar tendency of TSH elevation above the reference interval, but the different TSH elevation levels among the measurement methods suggested the existence of some interfering substance. Neither serial dilution of the patient's serum nor polyethylene glycol and protein G precipitation tests showed any significant changes in the recovery rate. IgG-bound macro-TSH was ruled out. The TSH peak on gel filtration chromatography was located at a molecular size greater than IgA, which suggested the presence of IgA-bound TSH. After precipitation with Jacalin, which binds specifically to IgA, the TSH level decreased from 30.7 µIU/mL to 2.01 µIU/mL, within the reference interval. Thus, IgA-bound macro-TSH was identified. Macro-TSH is a rare condition in which an immunoglobulin-bound, high-molecular-weight form of TSH results in a false elevation of the serum TSH level. When there is a discrepancy between the results of thyroid function tests and clinical symptoms, and macro-TSH is suspected, it is necessary to know that not only IgG-bound TSH but also IgA-bound TSH could be the cause.

Propylthiouracil-induced otitis media with anti-neutrophil cytoplasmic antibody-associated vasculitis: a case report and review of the literature.

Propylthiouracil (PTU)-induced otitis media with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (OMAAV) is an extremely rare adverse event associated with anti-thyroid drugs and is not well recognized. A 42-year-old woman with Graves' disease undergoing PTU therapy for 8 years visited our hospital because of earache and congested feeling in her left ear. Blood tests, a computed tomography scan and pure tone audiometry revealed otitis media and moderate mixed hearing impairment. Antibiotics, ear drops with antibiotics and painkillers were administered. However, her earache and hearing loss gradually got worse and symptoms of facial nerve palsy appeared. At several weeks after initiation of the treatment, a high serum level of myeloperoxidase (MPO)-ANCA, 75.6 U/mL, was revealed. After excluding other causes, she was diagnosed with OMAAV. PTU was suspected as the cause of her OMAAV and was immediately discontinued, and prednisolone was started. Hearing impairment in her left ear gradually got better and showed substantial improvement. Facial nerve palsy disappeared. Although PTU-induced OMAAV is an extremely rare disease, it is important to recognize the disease, as delayed treatment can lead to irreversible hearing loss, hypertrophic pachymeningitis, and subarachnoid hemorrhage. When patients taking anti-thyroid drugs, especially PTU, are diagnosed with refractory otitis media or hearing loss, it is possible that OMAAV might be the cause and thus serum ANCA levels should be evaluated.

Effect of long-term amiodarone treatment on thyroid function in euthyroid Japanese patients: a 12-month retrospective analysis.

Amiodarone is an effective antiarrhythmic drug. However, it is associated with changes in thyroid function in euthyroid patients due to its high iodine content and intrinsic drug effects. Studies have been conducted in iodine-deficient and iodine-sufficient countries; however, data from countries with excessive iodine intake are lacking. Thus, this study aimed to evaluate the effect of long-term amiodarone treatment on thyroid function in euthyroid Japanese patients. Japanese adults aged ≥18 years who were treated with amiodarone for at least 90 consecutive days were included in this retrospective chart review. Patients with abnormal thyroid function test results at baseline were excluded. Serial changes in thyroid function tests at baseline and at days 30, 90, 180, 270, and 360 were analyzed using a mixed-effects model for repeated measures. In total, 46 patients with a mean age of 63.7 years were evaluated. The mean TSH level significantly increased from 1.62 µIU/mL at baseline to 3.43, 2.75, 2.84, 2.78, and 2.65 µIU/mL at days 30, 90, 180, 270, and 360, respectively. The mean free T4 level significantly increased from 1.3 ng/dL at baseline to 1.4, 1.5, 1.5, 1.5, and 1.5 ng/dL at days 30, 90, 180, 270, and 360, respectively. The mean free T3 level significantly decreased from 2.8 pg/mL at baseline to 2.4, 2.3, 2.3, 2.4, and 2.4 pg/mL at days 30, 90, 180, 270, and 360, respectively. In conclusion, significant changes in thyroid function persisted not only in the acute phase but also in the chronic phase of long-term amiodarone treatment.

TRAb elevations occurred even in the third trimester; a case of a mother of a child with neonatal thyroid dysfunction, who received radioactive iodine therapy for Graves' disease.

Activity of Graves' disease (GD) is known to improve during gestation, as values of thyrotropin (TSH) receptor antibody (TRAb) also improve. However, the risk of neonatal hyperthyroidism increases when maternal TRAb values are high in the second to third trimester. A 29-year-old woman who had undergone radioactive iodine (RAI) therapy for GD 10 years earlier visited our hospital at 17 weeks of gestation, showing subclinical hypothyroidism and a positive TRAb value of 2.6 IU/L (reference range, <2.0 IU/L). Thyroid hormone replacement therapy was commenced and thyroid function normalized within 4 weeks, although TRAb was elevated at the time (3.8 IU/L). Prenatal check-up showed normal growth development and no irregularities. At 29 weeks of gestation, serum TRAb was extremely elevated, up to 16.8 IU/L. Since the risk of neonatal hyperthyroidism was of great concern, delivery was planned at an advanced-care medical center. At 38 weeks 5 days of gestation, she delivered a female neonate without any complications, although blood testing of the neonate showed subclinical hyperthyroidism with positive TRAb and TSH receptor stimulating antibody (TSAb). According to the American Thyroid Association guidelines, the TRAb value should be checked in the third trimester if mothers show a TRAb elevation between the initial visit after pregnancy and 18-22 weeks of gestation. However, if the mother has a history of RAI therapy for GD, regardless of thyroid function during gestation, the possibility of TRAb values elevating over time even years after the definitive therapy must be considered.

Therapeutic efficacy and limitations of potassium iodide for patients newly diagnosed with Graves' disease.

The efficacy of potassium iodide (KI) for Graves' disease (GD) has been reported, although few clinical reports have examined the long-term efficacy of treatment. The objective of this study was to investigate the efficacy and limitations of KI treatment for GD. This study enrolled patients newly diagnosed with mild GD, defined as free thyroxine (FT4) <5.0 ng/dL, between July 2014 and June 2016. KI was started at a dose of 50 mg/day, and if FT4 values did not decrease after initiation of treatment, doses were increased to 100 mg/day. Patients for whom thyroid hormone levels could not be controlled with KI at 100 mg/day were regarded as non-responders. Of the 122 patients (13 males, 109 females) included in this study, 71 (58.2%) responded to KI therapy. The remaining 51 patients (41.8%) were non-responders. The median duration required to judge non-responsiveness was 5.9 months. Multiple logistic regression analysis performed on parameters measured at the initial visit indicated FT4 (odds ratio (OR) 2.19, 95% confidence interval (CI) 1.28-3.75; p = 0.0007) and male sex (OR 3.58, 95%CI 1.04-12.3; p = 0.04) were significantly associated with KI responsiveness. Receiver operating characteristic (ROC) curve analysis of the relationship between FT4 and KI responsiveness indicated an FT4 cut-off of 2.76 ng/dL was optimal for differentiating between responders and non-responders. KI therapy was effective and safe for about 60% of patients with mild GD.

A case of familial dysalbuminemic hyperthyroxinemia (FDH) in Japan: FDH as a possible differential diagnosis of syndrome of inappropriate secretion of thyroid-stimulating hormone (SITSH).

Familial dysalbuminemic hyperthyroxinemia (FDH) is an autosomal dominant condition and is the most commonly inherited euthyroid hyperthyroxinemia in Caucasians. However, it is extremely rare in Asian populations. A 30-year-old Japanese woman, who was incidentally found to have apparent thyroid dysfunction, was admitted to our hospital in 2004. She had extremely elevated serum free thyroxine (FT4), moderately elevated free triiodothyronine (FT3), and normal thyroid-stimulating hormone (TSH). Clinical thyroid examination revealed no abnormalities other than small goiter. Anti-thyroglobulin antibody titer was positive, but titers of other anti-thyroid antibodies, including antithyroid peroxidase antibody, TSH receptor antibodies, and thyroid-stimulating antibody, were negative. Levels of FT3, FT4, and TSH were similar when measured by three different laboratory kits, and FT4 was still high when measured by equilibrium dialysis. By affinity chromatography, FT4, TT4, and albumin were extracted to the same fraction, and the levels of FT4 and TT4 were extremely high. By combination of reversed phase liquid chromatography and mass spectrometry techniques, the amino acid sequence of human serum albumin was determined. The patient was found to be a heterozygote for p.R218P mutation in the gene for human serum albumin and was diagnosed as FDH. This patient, who harbored the p.R218P mutation in the albumin gene, is the fifth case report of FDH in Japan. This condition is characterized by extremely high serum FT4 and moderately high serum FT3 levels. Although rare, FDH should be considered in the differential diagnosis for syndrome of inappropriate secretion of TSH (SITSH) in Japan.

Inhibitory effect of low-dose inorganic iodine on thyroidal radioactive iodine uptake in healthy Japanese adults.

In the event of a nuclear power plant accident, prophylactic administration of potassium iodide (KI) is recommended to prevent thyroid damage due to uptake of radioiodine. To assess the inhibitory effect of low-dose inorganic iodine on thyroidal radioactive iodine uptake (RAIU) in healthy adults without dietary iodine restriction, single or repeated doses of 10 mg inorganic iodine solution were given to 22 Japanese volunteers, 18 men and 4 women with the mean age of 35.7 years, between 2011 and 2013. Changes in urinary iodine excretion, thyroid function and 24-hour RAIU were also evaluated. The median 24-hour RAIU without iodine restriction was 13% (range, 5-26%). A single-dose of 10 mg inorganic iodine suppressed the median 24-hour RAIU measured one hour after iodine administration to 3% (range, 1-7 %) and, in 90.9% of 22 participants their 24-hour RAIU was < 5%. For seven participants given 10 mg of inorganic iodine daily for 14 days, the median 24-hour RAIU measured at 24 hours after the last administration of iodine was 6% (range, 2-12%), although the inhibitory effect was diminished in two participants. Serum thyroid stimulating hormone concentration was slightly elevated in three participants without decreased serum FT3 and FT4 levels. We conclude that a single-dose of 10 mg inorganic iodine is sufficient to inhibit RAIU in adults, although the inhibitory effect of repeated-dose on RAIU is diminished when KI is given once daily. The dose, duration or interval of iodine administration should be evaluated in iodine-sufficient regions in a future.

TSH receptor antibody titers measured with a third-generation assay did not reflect the activity of Graves' ophthalmopathy in untreated Japanese Graves' disease patients.

TSH receptor antibody (TRAb) titer has been reported to be correlated with Graves' ophthalmopathy (GO). However, the correlation between GO activity and TRAb titer assessed with a third-generation assay has not been reported. We enrolled 238 untreated Graves' disease patients who came to the outpatient clinic of Ito Hospital and 28 patients who were euthyroid. All of the patients were assessed for GO by an ophthalmologist within 3 months of their initial visit to Ito Hospital. Clinical activity score (CAS), short inversion time inversion recovery (STIR), and sum of the maximum external orbital muscle areas (SEOMA) on a frontal sectional magnetic resonance imaging (MRI). The TRAb titer was significantly higher in patients with inactive ophthalmopathy (the inactive-GO group) than in patients with active ophthalmopathy (the active-GO group) (17.7 ± 13.5 IU/L vs. 13.0 ± 13.1 IU/L, p=0.0082). The SEOMA values were not correlated with TRAb titer. The prevalence of active-GO was higher in euthyroid patients than in hyperthyroid patients although the difference was not significant. In conclusion, TRAb titer measured with a third-generation assay dose not correlate with GO activity based on MRI findings in untreated Graves' disease patients, and the prevalence of active-GO is higher in euthyroid patients with lower TRAb titers than in hyperthyroid patients.

The characteristics of osteoporotic patients in Graves' disease patients newly diagnosed after menopause: a prospective observational study.

Overt hyperthyroidism is associated with reduced bone density. The extent of restoration of reduced bone density caused by hyperthyroidism in postmenopausal Graves' disease (GD) patients has not fully been investigated. We examined 85 newly diagnosed postmenopausal GD patients, and we measured their serum thyroid hormone levels as well as their bone turnover marker levels and the bone mineral density (BMD) of their lumbar spine (LS), both femoral necks (FN), and left distal radius (DR). We prospectively observed the patients for changes in BMD and bone turnover marker levels during a 24-month period after euthyroidism had been established by ATD treatment. The median age of the subjects was 57 years old (range: 50 to 79). 46 (54.1%) patients had osteoporosis. 42 of the 46 osteoporosis patients had low BMD in the DR. The patients with osteoporosis were significantly older, had a significantly lower BMI, and had significantly higher bone turnover marker levels compared to the normal BMD patients. The best predictor of the BMD in the DR was BMD in the FN (ß = 0.40, p < 0.0001). A total of 42 patients were followed up for 24 months after attainment of euthyroidism, and 19 of them were osteoporosis at the first visit. The BMD of the 19 osteoporotic patients had increased by 4.9% in the LS, 11.9% in the FN, and 9.3% in the DR at 24 months. After maintaining a euthyroid state for 24 months by means of ATD treatment, 26% of the osteoporotic patients had recovered from osteoporosis.

An Evaluation of the Efficacy of Machine Learning in Predicting Thyrotoxicosis and Hypothyroidism: A Comparative Assessment of Biochemical Test Parameters Used in Different Health Checkups.

Objective This study assessed the efficacy of machine learning in predicting thyrotoxicosis and hypothyroidism [thyroid-stimulating hormone (TSH) >10.0 mIU/L] by leveraging age and sex as variables and integrating biochemical test parameters used by the Japan Society of Health Evaluation and Promotion (JHEP) and the Japan Society of Ningen Dock (JND). Subjects and Methods Our study included 20,653 untreated patients with Graves' disease, 3,435 untreated patients with painless thyroiditis, 4,266 healthy individuals, and 18,937 untreated patients with Hashimoto's thyroiditis. Machine learning was conducted using Prediction One on three distinct datasets: the Ito dataset (age, sex, and 30 blood tests and biochemical test data), the JHEP dataset (age, sex, and TP, T-Bil, AST, ALT, γGTP, ALP, CRE, UA, and T-Cho test data), and the JND dataset (age, sex, and AST, ALT, γGTP, CRE, and UA test data). Results The results for distinguishing thyrotoxicosis patients from the healthy control group showed that the JHEP dataset yielded substantial discriminative capacity with an area under the curve (AUC) of 0.966, sensitivity of 92.2%, specificity of 89.1%, and accuracy of 91.7%. The JND dataset displayed similar robustness, with an AUC of 0.948, sensitivity of 92.0%, specificity of 81.3%, and accuracy of 90.4%. Differentiating hypothyroid patients from the healthy control group yielded similarly robust performances, with the JHEP dataset yielding AUC, sensitivity, specificity, and accuracy values of 0.864, 84.2%, 72.1%, and 77.4%, respectively, and the JND dataset yielding values of 0.840, 83.2%, 67.2%, and 74.3%, respectively. Conclusions Machine learning is a potent screening tool for thyrotoxicosis and hypothyroidism.

Persistent high TRAb values during pregnancy predict increased risk of neonatal hyperthyroidism following radioiodine therapy for refractory hyperthyroidism.

Serum levels of TSH receptor antibody (TRAb) often increase after radioiodine treatment for Graves' disease, and high-serum levels of maternal TRAb in late pregnancy indicate a risk of neonatal hyperthyroidism. The aim of this retrospective study is to investigate the characteristics of Graves' women who had a history of radioiodine treatment for intractable Graves' disease, and whose neonates suffered from hyperthyroidism. The subjects of this study were 45 patients with Graves' disease who became pregnant during the period from 1988 to 1998 after receiving radioiodine treatment at Ito Hospital. 25 of the 45 subjects had had a relapse of hyperthyroidism after surgical treatment for Graves' disease. 19 pregnancies were excluded because of artificial or spontaneous abortion. In the remaining 44 pregnancies of 35 patients, neonatal hyperthyroidism developed in 5 (11.3%) pregnancies of 4 patients. Serum levels of TRAb at delivery were higher in patients whose neonates suffered from hyperthyroidism (NH mother) than those of patients who delivered normal infants (N mother). Furthermore, serum levels of TRAb in NH mother did not change during pregnancy, although those of 4 patients of N mother, in which serum levels of TRAb before radioiodine treatment were as high as in NH mother, decreased significantly during pregnancy. In conclusion, women who delivered neonates with hyperthyroidism following radioiodine treatment seem to have very severe and intractable Graves' disease. Persistent high TRAb values during pregnancy observed in those patients may be a cause of neonatal hyperthyroidism.

Severe thyroid-associated orbitopathy in Hashimoto's thyroiditis. Report of 2 cases.

Thyroid-associated orbitopathy (TAO) is characterized by immune-mediated inflammation of the extraocular muscles surrounding orbital connective tissue and adipose tissue. Severe orbitopathy related to autoimmune thyroid disease often occurs in patients with Grave's disease, but it is rare in patients with Hashimoto's thyroiditis. The pathogenesis of TAO is unclear. Several studies have noted a strong correlation between the levels of antibodies to thyrotropin receptor antibody (TRAb) and TAO in Graves' disease. Mild upper eyelid retraction has been reported to be common in Hashimoto's thyroiditis patients, however severe orbitopathy is rare. We report two cases of severe TAO in patients with Hashimoto's thyroiditis who required systemic glucocorticoid therapy and orbital irradiation to treat the TAO. The activity of the TAO was high in both patients, because their clinical activity scores (CAS) for the orbitopathy were high, and magnetic resonance imaging (MRI) showed enlargement of the extraocular muscles and an increase in T2 signal intensity and prolonged T2 relaxation time which indicate an active stage of inflammation. We tested the presence of TRAb by three different assays and were negative in both patients. Since the eye muscle damage cannot be due to TSH receptor antibodies, other pathogenetic mechanisms may be responsible for the orbitopathy in patients with Hashimoto's thyroiditis.